Combined ferrule and insulation holder for wires



March 22, 1938. u. c. DUNAWAY 2,111,760

\ COMBINED FERRULE AND INSULATION HOLDER FOR WIRES Filed Aug. '7, 1935 Yul/Euro [/LB/CH CZJUNA AY ATTORNEY Patented Mar, 22, 1938 a 2 111 7 UNITED ES PATENT. OFFICE.

COIWBINED FERRULE AND INSULATION HOLDEILFOR WIRES Ulrich .0. Dunaway, St. Louis, Mo; assignor to James R. Kearney Corporation, St. Louis, Mo., a corporation of Missouri Application. August 7, 1935, Serial No. 35,086

2 Claims. (01. 173-269) This invention relates generally to ferrules and for so holding the insulated portion of the coninsulation holders for electrical wires, and more ductor located adjacent to the ferrule-receiving specifically to' an improved device which provides stranded portion thereof as to prevent such movea combined. ferrule and insulation holder adapted ment of the conductor as would tend to break the for attachment tov an end portion of an electrical flexible strands at the end of the insulation. 5 conductor of the extra flexiblev stranded type Fig. 1 is a front elevation of the improved deprovided with heavy rubber insulation, the previce applied to a fragment of an electrical dominant object of the invention being to provide conductor.

a device of this sort which at once'provides the Fig. 2 is a side elevation of the structure illusflexible strands. at an end of such a conductor trated in Fig. 1. 10 With a protecting sleeve well adapted to receive Fig. 3 is a horizontal section on line 33 of in contact therewith set screws. and other clamp- Fig. 1. ing elements, andwhich includesmeans for hold- In the drawing, wherein is shown for the puring-and retaining inplacethe insulated portion pose of illustration, merely, one embodiment of of the conductorwhich is located adjacent to the invention, A designates the improved device 15 the stranded end portion of said conductor that generally. The device A comprises a head I is: received by saidlferrula: '1 l which includes an intermediate portion 2 from As is generally known by personsfamiliar with which a tapered portion 3 is extended. Projected such matters, electrical conductors are frequently outwardly from the tapered portion 3 is a sleeve 2 attached to clamps and other articles of elecportion 4, said sleeve portion preferably, though trical equipment with the aid of set-screws and not necessarily, also being slightly tapered. The

like clamplngelements. In the'caseofelectrical intermediate portion 2 and the tapered portion conductors of the type including very flexible 3 have formed therethrough a continuous openstrands ofconducting material enclosed within ing 5, and this opening communicates with a heavy rubber insulation, it-has' been found necesslightly larger opening 6 formed through the sary to providesome-means'such as a ferrule, for sleeve portion 4. Fixedly seated in any suitable enclosing the flexible stranded end portion of manner-intheopening 6 formed in the sleeve the conductor so that secure mechanical and 4 is a length of tubing 7 formed of copper or positive electrical contact may be obtained beother good electrical conducting material, the tween theclamping'elements and the conductor. opening-through said length of: tubing being of Need has also been felt for some means for clampsubstantially the same diameter as the opening 5 ing over the insulation of the conductor so as to formed through the intermediate and tapered prevent the very flexible strands of the conductor portions 2 and 3 of the head 1.

form breaking'at the end of the insulation due Extended from the intermediate portion 2 of to extreme flexibility at that point when the end the head I in the opposite direction to the direcof the conductor is clamped in place when in tion of extension of the tapered portion 3 and use. the sleeve 4 is a leg 8 which is of arcuate cross- I have therefore evolved the improved device section, as shown in Fig. 3. The leg 8 has formed disclosed herein which, briefly stated, comprises thereon ears 9 which extend outwardly from said 40 a unitary element in which is combined a ferrule leg in opposite directions, said ears having screw- 4 for receiving the flexible strands of the conductor threaded openings 9' formed therethrough. so that set screws and other clamping elements Associated with the leg 8 of the head I of the may be applied thereto, and means for receiving device A is a clamping element II), this clamping and clamping in place the insulated portion of the element also being of arcuate cross-section so as conductor which is located immediately adjacent to correspond to the cross-sectional shape of the 45 to the stranded ferrule-receiving portion of the leg 8 of the head I. The clamping element I0 is conductor. Thus the improved device provides provided with outwardly extended ears H which for a conductor adequate ferrule means for reare projected in opposite directions, said ears ceiving in contact therewith set screws and other being alined with the ears 9 of the leg 8. Also,

clamping elements, which ferrule means protects the ears ll of the clamping'element II] are pro- 5 the flexible strands of the conductor from injury vided with smooth openings l2 which are alined from the clamping elements and provides for sewith the openings 9' formed through the ears 9 cure and positive mechanical and electrical conof the leg 8. The openings l2 of the ears of the nection between the conductor and said clamping clamping element l0 and the openings 9' of the elements. Also, the improved device provides ears of the leg 8 receive clamping screws l3 which 55 pass through the smooth openings l2 of the ears of the clamping element Ill and are screwed into the screw-threaded openings 9 of the ears of the leg 8 so as to draw said clamping element into clamping relation with respect to the leg 8.

In the use of the improved device an exposed stranded end portion S of an electrical conductor is passed through the opening 5 formed in the head I of the device and is extended into the opening through the length of tubing 1, said ex posed stranded end portion of said conductor being soldered within said tubing. The'clamping element H), which is detached from the leg 8' when a conductor is being applied to the device A, is then arranged in place and the clamping screws [3 are passed through the openings l2 of the ears of the clamping element and are screwed into the openings 9 of the ears of the leg 8 to securely clamp the insulated portion of the conductor C between the arcuate portions of the clamping element and the leg. Thus the length of tubing 1 provides a ferrule which encloses the stranded end portion of the conductor, and this length of tubing may be introduced into a clamp or other element of electrical equipment and receive set screws or other clamping elements in contact therewith to provide secure mechanical and positive electrical connection between the conductor and said element of electrical equipment. Also because the insulated portion of the conductor is clamped and held in place by the clamping element l0 and the leg 8, no movement is permitted at the point where the exposed stranded end portion S extends from the insulation R4 of the conductor, hence breaking of the strands of the conductor at that point because of movement of the conductor is prevented.

I claim:

1. A device of the class described, comprising a unitary structure including a cylindrical head, said head being provided with an integral sleeve portion at one end of the main body portion thereof of reduced diameter and having an integral substantially semicircular extension at its opposite end the outer radius of which is substantially the same as the outer radius of the main body portion of said head, said head and sleeve portion having a continuous opening formed therethrough, a hollow element providing a ferrule which is fixedly supported in the opening formed in said sleeve portion and extends outwardly beyond said sleeve portion, said hollow element being adapted to receive an exposed stranded end portion of an electrical conductor, an arcuate clamping element associated with said extension in a manner to clamp an insulated portion of the electrical conductor between said clamping element and said extension so as to prevent movement of the clamped insulated portion of the conductor with respect to the stranded end portion thereof, and clamping bolts for drawing said clamping element toward said extension so as to clamp the insulated portion of the electrical conductor therebetween.

2. A device of the class described, comprising a unitary structure including a cylindrical head, said head being provided with an integral sleeve portion at one end of the main body portion thereof of reduced diameter and having an integral substantially semicircular extension at its opposite end the outer radius of which is substantially the same as the outer radius of the main body portion of said head, said head and sleeve portion having a continuous opening formed therethrough, a hollow element providing a ferrule which is fixedly supported in the opening formed in said sleeve portion and extends outwardly beyond said sleeve portion, said hollow element being adapted to receive an exposed stranded end portion of an electrical conductor, an arcuate clamping element associated with said extension in a manner to clamp an insulated portion of the electrical conductor between said clamping element and said extension so as to prevent movement of the clamped insulated portion of the conductor withrespect to the stranded end portion thereof, said clamping element having an outer radius substantially the same as that of the main body portion of the head and the arcuate outer surface of the clamping element being substantially alined longitudinally of the device with respect to the arcuate outer surface of the main body portion of the head, and clamping bolts for drawing said clamping element toward said extension so as to clamp the insulated portion of the electrical conductor therebetween.

ULRICH C. DUNAWAY. 

